BENCH TOOLS / 01

Numbers you can
use at the cabinet.

Small calculators for translating a reading into the next sensible question. No account. No spreadsheet ceremony.

FIELD
READY

4–20 mA converter

Translate a measured current into engineering units.

Measured current

Signal minimum

Signal maximum

Range minimum

units

Range maximum

units

FORMULAlow + ((mA − mAmin) ÷ (mAmax − mAmin)) × (high − low)

ENGINEERING VALUE50.000 to 100 range

4 mA20 mA

Inside the configured range. The signal is giving you a usable reading.

Estimate the voltage consumed by a known loop resistance.

Supply voltage

Loop resistance

At 12.00 mA, this resistance uses3.00 Vleaving approximately 21.00 V for the transmitter and input.

A quick handoff from number to next check.

Check scaling, range selection, and whether the input expects current or voltage.

Check routing near drives, shield termination, reference points, and loose terminals.

Check supply, polarity, continuity, and the input card’s live-zero configuration.